February 15, 2013

In this case, let’s imagine that the conclusion is a truly bad one—that our football-field sized rock would be targeting a populated area. And for the sake of doomsday pizzaz, let’s make that populated area New York City.

An 830 sq. mi blast ring has a radius of 14.4 mi. (23.2 km). Position that over New York City and you’d have destruction reaching deep into Queens in the east and Staten Island in the South; west to Paterson and Montclair, NJ; and north to Yonkers and New Rochelle, NY. Manhattan, the Bronx and Brooklyn would be swallowed whole. Evacuation in advance of the blast would be a massive challenge, since the array of bridges and tunnels that connect the boroughs are natural choke points. The many months of notice the residents would have before the big day arrived would make things a bit easier, but fleeing from an asteroid is very different from fleeing from other kinds of disasters. People evacuating in advance of, say, a hurricane can usually just load up their cars and go, since even after a superstorm like Katrina, most of them will simply be turning around and coming home. After a Tunguska-like blast, most people would not have any home left at all.

The bigger risk, of course, is that we get hit by one we don’t see coming, and that it’s bigger than the so-so Tunguska impact.

Meanwhile, reader Curt Johnson writes:

With asteroid hunting back in the news with the latest close approach, I thought you might be interested to know that after the Shoemaker-Levi event, I (with the support of TRW, for whom I worked at the time) designed a satellite mission we named IRASMES that would have detected every asteroid capable to threatening the Earth greater than 50-m in mean diameter. The mission would have taken about ten years from launch and would have cost less than $150 million. (Compare the cost of a single NASA or DOD launch in those days.) The mission would been completed around 2007.

My concept used American multispectral sensors and electronics on a Russian bus, and would have launched on a Russian booster. The Russian partner was Lavochkin. I presented to paper on this concept at a UN conference on the asteroid threat that was held in the wake of Shoemaker-Levi.

Of course, Congress would not fund the concept. Looks like others are starting to pick up the slack, almost 20 years on. So yes — faster, please.